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991.
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993.
Efforts to represent knowledge effectively have been central to progress in various aspects of medical informatics. These efforts range from relatively simple "electronic textbooks" to fairly sophisticated knowledge-based systems, which function as well as, or even better than, human experts faced with similar problems. Knowledge bases have been developed in many fields, but the relatively limited domains and structured language of medicine, as well as the importance of information in the provision of good medical care, have made research in medical knowledge representation an area of intense activity. This paper reviews representative knowledge bases and knowledge-based systems in medicine: electronic textbooks such as PDQ and the Hepatitis Knowledge Base (HKB), rule-based systems such as MYCIN, causal models (e.g., CASNET), and hypothesis- or frame-based systems, exemplified by PIP and INTERNIST-1. The paper describes the relationships among divergent approaches and provides a sense of current and future trends. It examines problems in knowledge-based systems, particularly in knowledge representation and acquisition, and the responses to these challenges. The latter include the use of domain-independent software shells for constructing knowledge bases, the adaptation and use of previously existing knowledge bases, and multiple uses of the same knowledge base for different purposes.  相似文献   
994.
In this paper, decomposition methods for multidimensional data hypercubes of OLAP systems are investigated. Criteria for reducing the computational complexity of the decomposition methods are presented and comparisons are made with the traditional solutions of multidimensional data analysis problems. Examples illustrating the application of these criteria to investigating the dynamics of computational complexity changes for specific types of reduction problems are considered.  相似文献   
995.
In this paper, a survey and critique are presented of the existing concepts of an information society. The concept of a “modern information society” is introduced. The main components of the information society concept are analyzed, i.e., information, information technologies and the IT workforce (specialists). Changes are considered in the main spheres of human activities. A broad definition of the modern information society is formulated.  相似文献   
996.
997.
The purpose of the study was to identify female students' attitudes toward mathematics when studying under four conditions and to assess the impact of school-type and sex of teacher on students' attitudes toward mathematics. An instrument to measure attitude toward mathematics was administered on a stratified random sample of 240 female students drawn from 5 co-educational and 6 all-girls' secondary schools in Plateau State, Nigeria. The findings suggest that the best environment under which females can learn mathematics is in all-girls' secondary schools where mathematics is taught by female teachers.  相似文献   
998.
Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.  相似文献   
999.
This study examines the relationships between the environmental attitudes and environmental knowledge of schoolchildren within the framework of an environmental intervention. We employed questions from the 2-MEV model to monitor students’ environmental attitudes in terms of the model factors Preservation and Utilisation while concurrently monitoring three environmental knowledge dimensions (system, action-related and effectiveness knowledge) at three different test times during the course of a four-day field centre programme for fourth-graders (N = 133, Mage = 9.8 years). Probably due to measurement constraints (e.g. a ceiling effect, social desirability), we found no correlation between environmental knowledge and the attitude Preservation at all test times. The attitude Utilisation correlated negatively with all environmental knowledge dimensions, indicating that students who score higher on Utilisation are more likely, for example, to have and gain more system knowledge through programme participation than the other students or vice versa, as a causal relationship cannot be derived from our analyses: system knowledge may also influence Utilisation. In other words, children who refrain from (ab)using nature also seem to put more effort into improving their environmental knowledge and/or children who engage in learning about the environment will become less exploitative towards the environment.  相似文献   
1000.
In the early 19th century, public libraries in America tended toward grand appearances befitting seriousness of purpose. Library design changed gradually throughout the 20th and 21st centuries, and more dramatically with automation and new technology. True to its roots, the public library continues to maintain areas for quiet, individual study. But, in addition, today’s library has become a cultural center in the community, offering art galleries, auditoriums, meeting rooms, spaces for collaborative work, digital information and instruction, and even cafés. Change is inevitable, as innovations in library design and patron use illustrate. Yet, from the earliest libraries to modern times, one overarching constant defines their purpose: libraries inspire.  相似文献   
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